Wire twisting device



'June 7, 1949. L. E. BENNETT WIRE TWIS'IING DEVICE Filed March 22, 1946 Patented June 7, 1949 WIRE TWISTING DEVICE Loren E. Bennett, Winnetka, Ill., assignor to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application March 22, 1946, Serial No. 656,332

Claims. 1

This invention relates to a wire twisting device and more particularly to a device for twisting the bared ends of stranded wire conductors.

When the insulation on stranded electrical conductors is stripped from the ends thereof, the strands of the bared wires become untwisted during the stripping operation and have to be reformed into a twisted tip in order to facilitate their attachment to terminals and soldering lugs. When done by hand, this, twisting operation is slow and ineficient.

It is an object of the present invention to provide a simple and effective device for quickly twisting the ends of stranded wire.

In one embodiment of the present invention, a rotary twisting member is formed from a relatively heavy wire and is fixed to and extends c0- axially from a motor shaft and has its free end shaped into a spiral hook into which the untwisted end of the stranded conductor may be moved radially and withdrawn axially to have the strands thereof frictionally twisted together.

A more complete understanding of the invention may be had by reference to the following detailed description considered in conjunction with the accompanying drawing, wherein Fig. 1 is a side elevational view of the wire twisting device showing a guide member thereon in section and showing a stranded conductor cord in position to enter the device;

Fig. 2 is a sectional view of the device taken on the line 2-2 of Fig. 1 showing the spiral hook of the wire twisting device in end elevation, the guide member in section and dot and dash lines, showing the outline of the radial guide slot in the guide member;

Fig. 3 is a fragmentary plan sectional view taken on the line 3-3 of Fig. 1 showing the Wire twisting device and a stranded wire conductor associated therewith; and

Fig. 4 is an elevational view of one end of a stranded wire conductor showing the relation of the strands after they have been twisted on themselves by the twisting device.

Referring to the drawing, wherein a preferred embodiment of the invention is illustrated, the wire twisting device comprises a wire twisting member l0 formed from a relatively heavy wire and having a straight shank H secured in coaxial relation to the end of a motor shaft 12 by a suitable chuck or collet IS. The shaft l2 projects horizontally from a motor M, which is mounted in a convenient position on a suitable support. At its free end, the member ID is provided with a spiral hook or finger l8 and is 2 adapted to be rotated about the axis of the shaft l2 and the shank H.

To form the hook it, the wire is bent laterally in a curved path, which gradually recedes from the aXis of rotation and advances progressively axially and angularly relative thereto to form substantially one complete convolution with the end is; thereof spaced a substantial distance from the axis. It will thus be seen that the hook I8 has a snail-shaped configuration and a strandengaging surface 23!, and toward the end 19 it has a relatively large curvature, which gradually decreases as it progresses inwardly to form a loop 2| adapted to snugly engage a portion of the periphery of the stranded wire. The twisting device I rotates in a counter-clockwise direction, as indicated in Fig. 2, and the end I9 of the hook l8 thereof, during its rotation, encircles a substantial area around the axis of rotation.

To guide the movement of a stranded end of a conductor cord radially into the hook 18; a guide member 36 is provided which also serves as a guard to prevent accidental engagement of the hook by the operator. The guide member comprises a cylindrical housing 3! secured to the motor M by a flange 32 and having an end wall 33 adjacent the hook it. A radially extending keyhole guide slot 35 is provided in the end wall 33, as indicated in Fig. 1, and in dot and dash lines in Fig. 2, and a slot 36, forming a continuation of the slot 35, is formed in the top portion of the cylindrical housing 3 I In a wire twisting operation, the strands 25 of a bared end of a stranded conductor cord 26 may be positioned above the rotating twisting device, as indicated in Fig. 2, and moved radially through the slots 35 and 36 of the guide member 30 into the path of the hook Ill. The strands 25 will be engaged by the curved surface 20 of the hook member l8 and will be moved toward the axis of rotation and into the loop 2| and by frictional engagement therewith will be carried along and twisted on themselves. The free ends of the strands 25 will be revolved about the shank ll of the rotating twisting member ID and the portions of the strands engaging the hook l8 and to the right of the hook will be twisted about themselves, as indicated in Fig. 3. As the conductor 26 is moved to the right and the strands 25 are withdrawn from the hook l8, successive portions thereof will be twisted so that when the strands 25 are entirely Withdrawn, they are reformed into the proper twisted shape, as indicated in Fig. 4.

What is claimed is:

1. A device for twisting the ends of stranded forming ailooprterminating at the'inward end" of the decreasing spiral and conforming substantially to a portion of the desired curvature of the stranded wire whereby the strands of the: stranded wire, when moved into engagement with the spirally formed surface of the twisting device, will be directed inwardly thereby toward the axis of rotation and into theiOOpihEreOf;

where they will be frictionally engaged'and" twisted about each other.

2. A device for twisting the ends of stranded wire comprising a member rotatable about a'fixed' axis and having a strand-engaging surface with onward-thereof spaced-from the axis of rotation; drive means for rotating said-member, said strandeengaging"-surface being formed in a decreasing;;spir-al inwardly-around and toward the axis.-..of-. rotation and? having aportion at the I inner: endihereofforming a loop conforming substantiallyto'aportionof the desired curvature ofethe strandedrwire-whereby the strands of the strandedn/vire, when'moved into engagement withtheispirally formed surface of-the twisting device, w-ilhbe directed inwardly thereby toward the axis oil rotation: and into the loop thereof, where thesewill be-frictionally engaged andtwisted about" eachrothengand a guard around said'rotatablet memberand-"having a"s1ot-' therein for guiding the strandedwire "into engagement with the rotatable. member.

3.5 A=-.device-for twisting the ends of stranded wire comprising: a-member rotatableabout a fixedeaxisxand having a strand-engaging'surfaceewith-ionez' end thereof spaced-fromrthep axisrofwrotation, and'drivemeans for rotating said.- member; said strand-engaging surface being.-.formed--.from the-"free end thereof spirally;

inwardlyiaround and toward the axis of "rotationr-andhaving a' portion at theinner end thereofsforminga loop eccentric with" respecttm-the :axis'ofr rotation and conforming sub v stantially to a portion of the desired curvature of the stranded wire whereby the strands of the stranded wire, when moved into engagement with the spirally formed surface of the twisting device, will be directed inwardly toward the axis of rotation and into the loop thereof, where they will be frictionally engaged andfrotated about the axis *of rotati'on of the device and" twisted about t each other.

4. A device for twisting the ends of stranded conductors comprising a wire member having an-.el0ngated shank portion and a spiral hook portion formed on one end thereof, and drive meanssat.theiiotherrend of said wire member and in spacedc relation to said hook for rotati'ng said wire-*m'ember about a fixed axis, said spiralv hook :portion being formed with each successive portion thereof starting at the juncturewith 'the shank portion curving progressively longitudinally forward and transversely awayrfrom*andccircumferentially around the axis of rotatiom 5. A device ifontwisting' the'ends of stranded conductorszcomprisinga wire'member having an elongated shank' portion anda spiral hook portion f orm'ed Olll .one zend thereof and drive means at the-otherendofi saidwire:member and in spaced relation'to sa'idshook fo'nrotatingsaid wire member-l about a fixedw axis-said spiral hook portion being:formemwi-theach successive portion thereof starting at the juncture with the-shank portion curving? progressivelyilongitudinally from said juncture and transverselyaaway. from and circumferentially around-the-axi's of rotation, and a guardmember 'aroundisaid .spiralhook "having aslot: therein: for-:guiding said: stranded conductors into engagement-with the rotatable hook.

LOREN" BENNETT.

REFERENCE S' CITED The following *refrences-areof record in the file of this -patntr- UNITED i STATES- PATENTS Nlimbel' Name P Date 304,299 Crabh-L Sept/2, 1884 347,562 Briggs-1; Aug. 17, 1886 1,436,637- Bates: Nov; 28, 1922 

